Conventionally, as a transport means for transporting workpieces or the like, a fluid pressure cylinder has been used having a piston that is displaced under the supply of a pressure fluid.
With a fluid pressure cylinder of this type, recently, from the standpoint of energy conservation, a demand has arisen to reduce the amount of pressure fluid that is used. For responding to such a demand, for example, with the fluid pressure cylinder disclosed in Japanese Laid-Open Patent Publication No. 08-042511, a supply unit that supplies the pressure fluid is connected through a switching valve to two cylinder chambers. In the case that a piston is displaced in one direction, under a switching action of the switching valve, the pressure fluid is supplied at a desired pressure to one of the cylinder chambers from a pressure fluid supply source, whereby the piston is displaced. Along therewith, a piston rod is displaced so as to become accommodated in the interior of the cylinder body.
On the other hand, in the case that the piston is displaced in the other direction, under a switching action of the switching valve, the pressure fluid from the one cylinder chamber is supplied to the other cylinder chamber, and the piston is pressed and displaced in the other direction through another end surface of the piston, which has a larger pressure-receiving area than the one end surface of the piston that faces toward the one cylinder chamber. In this manner, normally, the piston is displaced in the other direction using the pressure fluid that is discharged to the exterior, whereby the amount of consumption of the pressure fluid is reduced.